It doesn't look like a tampon string. I've seen plenty. In fact, I use to have a girlfriend that would let me put them in. I love the way you put that thing in, then slide the tube, then pull out the plastic . . . ingenious!

Anyway, the ones I've seen are just one string hanging out with a square paper tab on the end.

This looks different, for some reason. Maybe she is using brasilian tampons, that double as tranny cocks.